AAT1147 Datasheet, PDF (7/18 Pages) Advanced Analogic Technologies – High Efficiency, Low Noise, Fast Transient 400mA Step-Down Converter

DATA SHEET
AAT1147
High Efficiency, Low Noise, Fast Transient 400mA Step-Down Converter
Typical Characteristics
No-Load Quiescent Current
vs. Input Voltage
220
210
200
25°C
190
85°C
180
170
160
150
-40°C
140
130
120
2.5
3.0
3.5
4.0
4.5
5.0
5.5
Input Voltage (V)
Line Transient Response
(40mA to 400mA; V_IN = 3.6V; V_OUT = 1.8V;
C₁ = 4.7µF; C_FF = 100pF)
2.0
1.4
1.9
1.2
1.8
1.0
1.7
0.8
1.6
0.6
1.5
0.4
1.4
0.2
1.3
400 mA
0.0
1.2
-0.2
40 mA
1.1
-0.4
1.0
-0.6
Time (25µs/div)
Line Transient Response
(40mA to 400mA; V_IN = 3.6V;
V_OUT = 1.8V; C₁ = 4.7µF)
2.0
1.4
1.9
1.2
1.8
1.0
1.7
0.8
1.6
0.6
1.5
0.4
1.4
0.2
1.3
400mA
0.0
1.2
-0.2
40mA
1.1
-0.4
1.0
-0.6
Time (25µs/div)
Soft Start
(V_IN = 3.6V; V_OUT = 1.8V; I_OUT = 400mA)
5.6
3.6
4.8
3.2
4.0
2.8
3.2
2.4
2.4
2.0
1.6
1.6
0.8
1.2
0.0
0.8
-0.8
0.4
-1.6
0.0
-2.4
-0.4
Time (25µs/div)
Line Response
(V_OUT = 1.8V @ 400mA)
1.90
5.2
1.85
5.0
1.80
4.8
1.75
4.6
1.70
4.4
1.65
4.2
1.60
4.0
1.55
3.8
1.50
3.6
1.45
3.4
1.40
3.2
Time (25µs/div)
Output Ripple
(V_IN = 3.6V; V_OUT = 1.8V; I_OUT = 400mA)
40
0.9
20
0.8
0
0.7
-20
0.6
-40
0.5
-60
0.4
-80
0.3
-100
0.2
-120
0.1
Time (500ns/div)
Skyworks Solutions, Inc. • Phone [781] 376-3000 • Fax [781] 376-3100 • [e-mail] • www.skyworksinc.com
201986A • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • May 23, 2012
7